Adoption is low and slow: because there is a push to sell customers stuff without providing clarity on the benefits to the customer. It's hard to convince a customer that savings of $25/year on your energy can justify a $100 expense on a device. It's even more difficult to sell most people on the need for a connected smoke detector when they hardly notice their current one until the battery runs down and it starts to make that dreadful how-can-I-break-this-device sentiment inducing noise. Save less than you spent on the energy saving device does not make for a compelling marketing message..

Interoperability: there are competing devices and standards, there is no Operating System (OS) for this space as of yet. The players are trying to solve this either through the Thread consortium approach or through a home hub device approach. The focus so far has been on making it easier for the provider and not the customers; my mother in law does not care about your standard because, guess what, she's not buying a standard or platform. This feels very much like the betamax vs VHS battle (if you're my age you'll remember) or Blue Ray vs HD DVD battles. Like a few other analysts, I think there won't be one winner here. There will be a few standards and platforms that cater to specific use cases.

The two issues above are anchored by the same core keylog; what my mother in law (and the average consumer) cares about is that her home and any technology in it maintains her sense of self esteem while she stays reassured of her well being and safety, without stripping her of her sense of control. The promise of the connected home currently makes consumers feel like they are not empowered in their own home and it's to the benefit of the device seller.